The production of microspheres containing active agent(s) is described in co-owned U.S. Pat. No. 5,683,720, incorporated herein by reference. The patent deals with the use of liquiflash processing to spheronize compositions containing one or more active agents. Acetaminophen is mentioned in Examples II and III of the patent.
EPO publication 0559 897 discloses quick release dosage forms made by coating drugs with a mixture of carnauba wax and Pluronics. The coating is said to taste mask the drug and enhance its release.
EPO publication 0353045 shows subcutaneous implants based on pellets containing somatropin, Pluronic surfactant and carnauba wax. See Example 3 therein.
In the past, the processability of tabletable compositions was enhanced by using glycerine, as a binding agent, to lend stickiness to the formulations. Some stickiness is desirable, serving to provide cohesion to hold the ingredients together during shaping and/or compression. However, in certain situations, glycerine can produce too much stickiness, resulting in the formulations' clumping or sticking in various machine parts before and during shaping and compression.
The excessive stickiness caused by the use of binders, e.g., glycerine, is overcome by employing self-binding compositions. Self-binding, readily flowable compositions containing no glycerine are described in U.S. Ser. No. 08/915,068, filed Aug. 20, 1997, now U.S. Pat. No. 5,840,331 and U.S. Ser. No. 08/914,972, also filed Aug. 20, 1997.
One way to provide self-binding flowable formulations is to formulate using shearform matrices or flosses. These matrices result when using certain processing techniques, such as the following:
U.S. Pat. No. 5,587,172, incorporated herein by reference, discusses the use of flash heat techniques to produce sucrose-containing shearform flosses, which are then processed to yield quick-dissolving tablets.
The use of shearform matrices for forming comestible units is described in WO95/34290 (published Dec. 21, 1995) from co-assigned PCT application No. PCT/US95/07144, filed Jun. 6, 1995. This case discloses a quick dissolving tablet which is formed by: (1) using flash-flow technology to provide a shearform matrix; (2) combining the partially recrystallized shearform matrix with an additive to form flowable, compactible particulate blends; and (3) compacting the blends at relatively low pressures to produce dosage forms, such as tablets.
Additionally, PCT publication WO 95/34293 (published Dec. 21, 1995) from co-assigned PCT Application No. PCT/US95/07194, filed Jun. 6, 1995, discloses a process and apparatus for making rapidly dissolving dosage forms by flash-flow processing. In this PCT application, a shearform matrix is formed by the flash-flow process, the shearform matrix is combined with an additive, and the matrix is molded to make a unit dosage form.
While shearform matrices are an advance in the art, there still exists a need for non-sticking tabletable compositions which, can be used to make fast-dissolving, pleasant tasting dosage forms. This invention addresses that need.